Global Patent Index - EP 0146647 B1

EP 0146647 B1 19871104 - METHOD OF PROCESSING MEASURED VALUES OF A GAS FRICTION VACUUM METER, AND A GAS FRICTION VACUUM METER PROVIDED WITH A CIRCUIT FOR CARRYING OUT THIS METHOD

Title (en)

METHOD OF PROCESSING MEASURED VALUES OF A GAS FRICTION VACUUM METER, AND A GAS FRICTION VACUUM METER PROVIDED WITH A CIRCUIT FOR CARRYING OUT THIS METHOD

Publication

EP 0146647 B1 19871104 (DE)

Application

EP 83112728 A 19831217

Priority

EP 83112728 A 19831217

Abstract (en)

[origin: US4640136A] A method for the processing of values measured in a gas friction vacuum meter, in which the pressure is determined by the drag on a magnetically suspended free ball, by forming a first time value tn-1 by measuring the time required for N/2 periods of revolution of the ball, and a second time value tn by the immediately following measurement of the time required for another N/2 periods of revolution of the ball, determining a pressure value by comparing the two times values, repeating this pressure value determination of two time values after each period of rotation for the same number N of periods of revolution of the ball to a total of z determinations, and displaying the average of the pressure value determined Z times. To be able to determine the pressure with optimum measurement times and uncertainties of measurement, the ratio of N to Z is selected at approximately 4:1.

IPC 1-7

G01L 21/24

IPC 8 full level

G01L 21/16 (2006.01); G01L 21/24 (2006.01)

CPC (source: EP US)

G01L 21/24 (2013.01 - EP US)

Designated contracting state (EPC)

CH DE FR GB LI

DOCDB simple family (publication)

EP 0146647 A1 19850703; EP 0146647 B1 19871104; DE 3374346 D1 19871210; JP S60168032 A 19850831; US 4640136 A 19870203

DOCDB simple family (application)

EP 83112728 A 19831217; DE 3374346 T 19831217; JP 26467484 A 19841217; US 68037884 A 19841211